JPH0973416A - IC card - Google Patents

Abstract

(57) [Abstract] [Problem] To improve the memory usage efficiency of key data and realize state management of key data. An IC card stores a plurality of related key data in a data area of a key data file storing key data. With related multiple key data,
For example, a password for file access control,
These are a read authority password, a write authority password, an issuer authority password, etc. Further, the encryption key and the decryption key, or the internal authentication key and the external authentication key used for mutual authentication between different IC cards are also mutually related key data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card, and more particularly, to an IC card having excellent security management, memory efficiency and processing efficiency.

[0002]

2. Description of the Related Art IC cards are excellent in that they have a large storage capacity and high security, and are expected in the future. By the way, the security management of the IC card is performed by using each key such as a password key, an authentication key, and an encryption / decryption key, and these key data are stored in the form of an internal basic file for use. To be done. The password key is mainly used for file access control, and the authentication key is mainly used for encryption authentication.
Decryption keys are mainly used to encrypt and decrypt data. The encryption / decryption key is used, for example, when using the delivery key.

Of these internal basic files, the most commonly used one is a file in which a password key for file access control is stored. Therefore,
Using this key file for password as an example, the conventional usage of key data will be described below. The security management of the data stored in the IC card is such that the data file cannot be accessed unless the data is stored in the data file and the access right is acquired by password verification. The password (password) required for a certain access to one data file also uses a plurality of passwords, and the form of access, that is, reading,
Security is ensured by controlling access to the data file by changing the password to be used by writing, updating, etc. Further, the password key used in password verification is also a kind of data, one password key is stored in one password key file, and the password key file is also a file subject to access control.

In general, a file is composed of a directory area and a data area, data to be stored and a password key are stored in the data area, and a file ID for identifying the file and other information are stored in the directory area. To be done. In the case of a key file such as a password key file as an internal basic file, as shown in FIG. 2, the key data for the password is stored in the data area, and the directory area has the file ID and the password verification maximum. The number of errors, an error counter, and a verification block flag indicating whether or not the password verification function can be executed are also stored.
Password verification cannot be executed when the verification function is blocked. This is because when the password verification is repeated with an incorrect password, the password error counter counts, and when the value of the counter reaches the maximum number of password verification errors, the verification block flag is set and the block status occurs, and the subsequent password verification is not accepted. Is to do. A password key file used for file access control of a certain data file is usually defined by a file access control table stored in a separate file.

[0005]

By the way, for example, in the above-mentioned password key file, the password collation fails for the owner password of the passwords, and the prescribed number of password collation (maximum number of errors).
If the password exceeds the limit, the password collating function is blocked, and thereafter, the operation using the password cannot be executed, and the IC card cannot be used. In order to restore this IC card so that it can be reused, it is necessary to cancel the blocked state, but it can be canceled only by a specific administrator. In this case, the issuer of the IC card often sets a new password for collation block cancellation in the IC card, that is, adds a new password file for collation block cancellation that stores the password for collation block cancellation. Then, using this verification block release password, a specific administrator releases the block state,
It is designed to be reused. From the viewpoint of security, a plurality of passwords are usually used as described above, but among them, it is important that the management password such as the collation block release password is not illegally used by a third party.

When a verification block release password file is newly provided, as shown in FIG. 3, a file newly composed of a directory area and a data area is consumed by the memory of the IC card for purposes other than the original data storage. To be done. Note that FIG. 3 shows that the owner password file and the collation block password file are occupied in the memory space, and the files and data therefor are occupied in the memory spaces above and below these files. The file ID in the directory area of the owner password file is information that the file is the owner password file, the verification block flag A indicates the block state of the verification function for the owner password, and the data area stores the owner password. To be done. Similarly, in the collation block release password file, the file ID indicating the file and the collation block flag B indicating the block state of the collation function for the collation block release password are set in the directory area, and the collation block release is set in the data area. Password is stored.

Further, in terms of security management, the collation block release password file itself in which the collation block flag (collation block flag A) of the owner password file and the collation block release password for releasing the collation block flag are stored. The check block flag (check block flag B) is closely related to each other in terms of usage. However, as shown in FIG. 3, if they are set as separate files, it is difficult to manage the state of both flags, that is, to check and manage them with the OS of the IC card. This is because the management of the block state of both password files by the OS of the IC card is premised on that and the OS needs a function of checking the block state of a specific password file. This check function is, for example, a search for a password file or a check of its block state. That is, a normal IC card is designed in the initial state on the assumption that the IC card issuer sequentially adds and sets necessary files in a file that manages the entire IC memory called a main file. ing. Therefore, in order to manage the block state by the OS, it is indispensable to search and check the two files on the OS and set the two files as related files at the time of issuing. Alternatively, when the cancellation password file is set later, it is necessary that the unmanaged cancellation password file can be managed by the OS as a file related to the (already set) password file.

[0008]

A first aspect of the IC card of the present invention has a structure in which a plurality of related key data are stored in a data area of a key data file storing the key data. A second invention of the IC card of the present invention is the IC card of the above-mentioned first invention, wherein a plurality of related key data are at least a read authority password, a write authority password, and a password for file access control. It is configured to be two or more passwords among the administrator authority passwords. A third invention of the IC card of the present invention is the IC card of the first invention, wherein a plurality of related key data is an internal authentication key and an external authentication key used for mutual authentication between different IC cards. There is a certain configuration. A fourth invention of the IC card of the present invention is configured such that, in the IC card of the first invention, a plurality of related key data are an encryption key and a decryption key.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An IC card embodiment of the present invention will be described below with reference to the drawings based on some embodiments.

First, the IC card of the present invention is characterized in that related key data is stored in the key data area of one key data file (internal basic file).
As described below, it is preferable to store key data that are closely related to each other in a single file. In the case of a key data file, the collation block flags related to the collation function of the key data are also stored in the directory area of the file, so the collation block flags for each key data that are stored together in one file are also stored together in the directory area. By doing so, it is possible to efficiently manage the related key data and the matching block flag, and various processes using them.

First, FIG. 1 shows the contents of a file in the IC memory when a holder password and a collation block flag releasing password for the collation block flag of the holder password are combined into one file as key data. It is an explanatory view which explains notionally. In the example of FIG. 1, the file names that have been combined into one, that is, the file ID
Is a holder password file, and the collation block release passwords are collected in a holder password file. As a result, as shown in the figure, the data area stores the owner password and the collation block cancellation password (for canceling the block when the collation function of the owner password is blocked) which are related to each other. It Further, in the directory area, the file ID for identifying the owner password file, the collation block flag A for the owner password, and the collation block flag B for the collation block flag releasing password are the same directory. Since they are put together in one, the management check by the OS of the IC card becomes easy. In addition to these, the maximum number of password collation errors and the error counter shown in FIG. 2 are also stored in the direct area of FIG. 1 for each password. Further, the file in which the holder password and the collation block releasing password of FIG. 1 are collected is shown in FIG.
It corresponds to the conventional file usage in which each password of is stored in an independent file. In this way, as shown in FIG. 1, by storing a plurality of matching block flags corresponding to a plurality of key data stored in the data area in one directory area, the memory capacity is saved.

An embodiment of the key data file of the IC card of the present invention described below is a collection of key data for access control to the data file in one file as shown in FIG. In the example of FIG. 4, the read password, the write password, and the issuer password are stored as one file in the data area of the data access password file. Although only the file ID is explicitly shown in the directory area in FIG.
As shown in FIG. 2, the maximum number of password collation errors, the error counter, the collation block flag, etc. are stored in the directory area for each password.

FIG. 5 shows the contents of a key data file in another embodiment of the present invention. In FIG. 5, IC card A and IC card B which are related to each other are used.
In one IC card, the internal authentication key and the external authentication key are combined into one mutual authentication key file (for each IC card). An internal authentication key and an external authentication key are stored in each of the IC cards A and B. Note that the mutual authentication is a method in which A (hereinafter referred to as an IC card A) and B (hereinafter referred to as an IC card B) prove their mutual validity. Then, in mutual authentication using encryption, the above internal authentication key and external authentication key are used as encryption keys. In other words, A and B have the same "encryption algorithm [for example, DES (Data Encryption
Ion Standard) and FEAL (Fast D)
ata Encipherment Algorithm
m) etc.] ”and an“ encryption key ”, the“ same result ”is output by the cryptographic calculation of the“ same numerical value ”. In mutual authentication, the same random numbers are exchanged on both sides, and the results of these two cryptographic calculations are compared with each other to authenticate their validity. B
When certifying the authenticity of (to A), the external authentication key of A and the internal authentication key of B are used. That is, the random number generated in A is transmitted to B, B performs calculation with the received random number using the internal authentication key, and transmits the calculation result to A. In A, the calculation by the random number to be transmitted is performed by the external authentication key, and the calculation result is compared and collated with the calculation result transmitted from B. Similarly, in order to prove the legitimacy of A, the internal authentication key of A and the external authentication key of B are used, the random number generated in B is transmitted to A, and A transmits the calculation result to B. .
In this way, A and B use two encryption keys (external authentication key and internal authentication key).

FIG. 6 also shows the contents of a key data file in another embodiment of the present invention. In FIG. 6, an IC card in which an IC card A and an IC card B perform encryption and decryption is shown. is there. In two IC cards, IC card A and IC card B, which are mutually related, the encryption key and the decryption key are collected (for each IC) as one encryption related key file. An encryption key and a decryption key are stored in each of the IC cards A and B. These keys are, for example, encrypted with the encryption key of the IC card A and passed to the IC card B, and the IC card B decrypts the encrypted information with the decryption key to restore the original information. . On the contrary, IC card B
From IC card A to IC card A is also encrypted with IC card B and decrypted with IC card A.

As described above, there are various combinations of related key data, but the related key data of the present invention and the combination thereof are not limited to these. Further, as described above, since the related key data can be managed in one file / directory area, it is not necessary for the OS to refer to the states of two files at the same time, which is advantageous in file processing and memory efficiency.

[0016]

According to the IC card of the present invention, key data related to one key data file is stored together, so that memory usage efficiency, security management, and processing efficiency are improved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a key data file in an embodiment of an IC card of the present invention.

FIG. 2 is an explanatory diagram showing a file structure of an internal basic file that stores key data in the memory of the IC card.

FIG. 3 is an explanatory diagram illustrating memory consumption in a conventional IC card.

FIG. 4 is an explanatory view showing related key data (access control key data) in another embodiment of the IC card of the present invention.

FIG. 5 is an explanatory diagram showing related key data (mutual authentication key data) in another embodiment of the IC card of the present invention.

FIG. 6 is an explanatory view showing related key data (encryption related key data) in another embodiment of the IC card of the present invention.

Claims (4)

[Claims] 1. An IC card having a plurality of related key data stored in a data area of a key data file storing the key data. 2. A plurality of related key data are two or more passwords for at least a read authority password, a write authority password and an issuer authority password as passwords for file access control. IC card described in 1. 3. A plurality of related key data have different I
2. The IC card according to claim 1, which is an internal authentication key and an external authentication key used for mutual authentication between C cards. 4. The IC card according to claim 1, wherein the plurality of related key data are an encryption key and a decryption key.